jrtonkin
Contributor
I'm a new diver, and looking to buy a BC, and would like a bit of advice on how much lift is necessary.
Kinds of diving:
mostly cool (45 to 65 degF) fresh water
mostly rental gear, at least initially, so
probably AL80 tanks
I'm looking at getting a BP setup, for two reasons:
Extensible to whatever diving I ever get into. Sure, for the moment I'm just doing "ooohh, look-it the pretty fish" (Or, given that it's great-lakes, "ooohh, look at the pretty rocks, silt, and mud") but eventually... <insert dream here>
Mobility. The biggest thing I noticed in my OW class was the *drastic* reduction in how easily I could move through the water... that was with a jacket-style BC, hopefully the BP will be better.
(By the way, any dealers in SW. Ontario who stock BPs and have a pool I can try them out in, let me know, my closest LDS doesn't seem to carry them)
Anyways, enough about what & why, now for the question:
How much lift beyond neutral do I need to keep my head comfortably out of the water? Yes, the goal is to spend time underwater, but in case of emergency, or any last-minute discussion, or (when I get around to taking advanced classes, for listening to in-water instruction), I'd like to be able to float with my head clear of the water.
Now some math...
Figuring my approximate proper weighting:
Body: -2 to +2 lb bouyancy, depending on day
Wetsuit: +5 (approx for a 7mm john & jacket)
Tank: +5 when empty.
Total: +12 lb at the end of the dive, so I
need that much to be neutral at the safety
stop.
Now for start-of-dive bouyancy
Body: -2
Wetsuit: 0 (assuming it compresses totally)
Tank: -2
Weightbelt: -12
Total: -14 lb, not counting incidentals like
mask, fins, reg.
Halcyon makes an 18lb wing, and from the point of view of maximizing streamlining, that'd be the best choice, BUT... that's only 4 lb more than my total negative bouyancy; is that enough of a safety factor?
The 18lb wing is also cheaper than the 27, and if it'll be sufficient for all thediving I'm going to do in the next few years, it'd be nice to save myself the money.
(I know I'm ignoring the fact that the wetsuit wouldn't be compressed at the surface... but I also left some gear out of the calculation, and that gives me a safety margin)
Thanks for any advice (or pointers to where I've gone horribly wrong in my math in the first case)
Jamie
Kinds of diving:
mostly cool (45 to 65 degF) fresh water
mostly rental gear, at least initially, so
probably AL80 tanks
I'm looking at getting a BP setup, for two reasons:
Extensible to whatever diving I ever get into. Sure, for the moment I'm just doing "ooohh, look-it the pretty fish" (Or, given that it's great-lakes, "ooohh, look at the pretty rocks, silt, and mud") but eventually... <insert dream here>
Mobility. The biggest thing I noticed in my OW class was the *drastic* reduction in how easily I could move through the water... that was with a jacket-style BC, hopefully the BP will be better.
(By the way, any dealers in SW. Ontario who stock BPs and have a pool I can try them out in, let me know, my closest LDS doesn't seem to carry them)
Anyways, enough about what & why, now for the question:
How much lift beyond neutral do I need to keep my head comfortably out of the water? Yes, the goal is to spend time underwater, but in case of emergency, or any last-minute discussion, or (when I get around to taking advanced classes, for listening to in-water instruction), I'd like to be able to float with my head clear of the water.
Now some math...
Figuring my approximate proper weighting:
Body: -2 to +2 lb bouyancy, depending on day
Wetsuit: +5 (approx for a 7mm john & jacket)
Tank: +5 when empty.
Total: +12 lb at the end of the dive, so I
need that much to be neutral at the safety
stop.
Now for start-of-dive bouyancy
Body: -2
Wetsuit: 0 (assuming it compresses totally)
Tank: -2
Weightbelt: -12
Total: -14 lb, not counting incidentals like
mask, fins, reg.
Halcyon makes an 18lb wing, and from the point of view of maximizing streamlining, that'd be the best choice, BUT... that's only 4 lb more than my total negative bouyancy; is that enough of a safety factor?
The 18lb wing is also cheaper than the 27, and if it'll be sufficient for all thediving I'm going to do in the next few years, it'd be nice to save myself the money.
(I know I'm ignoring the fact that the wetsuit wouldn't be compressed at the surface... but I also left some gear out of the calculation, and that gives me a safety margin)
Thanks for any advice (or pointers to where I've gone horribly wrong in my math in the first case)
Jamie
